In this work the flake-materials (thickness=4mm and 1.2mm) of lower density PE are selected as samples. By putting them in aqueous solution of acrylic acid,the graft copolymerization is completed by ,60,Co γ-irradiation. So on the surfaces of flake-samples the monomer of acrylic acid is grafted, and the samples surfaces are transformed from non-polar ones to the ones with polar groups. Thus the surface-adhesiveness of PE flake-material is modified much better. With different adhesives,the adhere-links of modified and primary flake-samples are accomplished respectively,then the surfaces adhesive strength of them is measured. The measured results show that the surface-adhesiveness of modified flake-samples is much better than that of primary samples.